mirror
/
transmission
mirror of https://github.com/transmission/transmission
1
0
Fork 0
Code Issues Releases Wiki Activity
transmission/libtransmission/web.c

805 lines
23 KiB
C
Raw Blame History

/*
* This file Copyright (C) 2008-2010 Mnemosyne LLC
*
* This file is licensed by the GPL version 2. Works owned by the
* Transmission project are granted a special exemption to clause 2(b)
* so that the bulk of its code can remain under the MIT license.
* This exemption does not extend to derived works not owned by
* the Transmission project.
*
* $Id$
*/
#include <assert.h>
#include <curl/curl.h>
#include <event.h>
#include <evdns.h>
#include "transmission.h"
#include "net.h"
#include "ptrarray.h"
#include "session.h"
#include "trevent.h"
#include "utils.h"
#include "version.h"
#include "web.h"
enum
{
TR_MEMORY_TRASH = 0xCC,
DEFAULT_TIMER_MSEC = 250, /* arbitrary */
MIN_DNS_CACHE_TIME = 60 * 60 * 24
};
#if 0
#define dbgmsg(...) \
do { \
fprintf( stderr, __VA_ARGS__ ); \
fprintf( stderr, "\n" ); \
} while( 0 )
#else
#define dbgmsg( ... ) \
do { \
if( tr_deepLoggingIsActive( ) ) \
tr_deepLog( __FILE__, __LINE__, "web", __VA_ARGS__ ); \
} while( 0 )
#endif
/***
****
***/
struct tr_web
{
tr_bool closing;
tr_bool haveAddr;
int taskCount;
long timer_msec;
CURLM * multi;
tr_session * session;
tr_address addr;
tr_ptrArray dns_cache;
struct event timer_event;
};
struct dns_cache_item;
static void dns_cache_item_free( struct dns_cache_item * );
static void
web_free( tr_web * g )
{
evdns_shutdown( TRUE );
curl_multi_cleanup( g->multi );
evtimer_del( &g->timer_event );
tr_ptrArrayDestruct( &g->dns_cache, (PtrArrayForeachFunc)dns_cache_item_free );
memset( g, TR_MEMORY_TRASH, sizeof( struct tr_web ) );
tr_free( g );
}
/***
****
***/
struct tr_web_task
{
int port;
unsigned long tag;
struct curl_slist * slist;
struct evbuffer * response;
char * url;
char * resolved_url;
char * host;
const char * resolved_host;
char * range;
tr_session * session;
tr_web_done_func * done_func;
void * done_func_user_data;
struct event timer_event;
CURL * easy;
CURLM * multi;
tr_bool timer_event_isSet;
};
static void
task_free( struct tr_web_task * task )
{
if( task->slist != NULL )
curl_slist_free_all( task->slist );
if( task->timer_event_isSet )
evtimer_del( &task->timer_event );
evbuffer_free( task->response );
tr_free( task->host );
tr_free( task->range );
tr_free( task->resolved_url );
tr_free( task->url );
memset( task, TR_MEMORY_TRASH, sizeof( struct tr_web_task ) );
tr_free( task );
}
/***
****
***/
struct dns_cache_item
{
char * host;
char * resolved_host;
time_t expiration;
tr_bool success;
};
static void
dns_cache_item_free( struct dns_cache_item * item )
{
if( item != NULL )
{
tr_free( item->host );
tr_free( item->resolved_host );
memset( item, TR_MEMORY_TRASH, sizeof( struct dns_cache_item ) );
tr_free( item );
}
}
static int
dns_cache_compare( const void * va, const void * vb )
{
const struct dns_cache_item * a = va;
const struct dns_cache_item * b = vb;
return strcmp( a->host, b->host );
}
typedef enum
{
TR_DNS_OK,
TR_DNS_FAIL,
TR_DNS_UNTESTED
}
tr_dns_result;
static void
dns_cache_clear_entry( struct tr_ptrArray * cache, const char * host )
{
struct dns_cache_item key;
key.host = (char*) host;
dns_cache_item_free( tr_ptrArrayRemoveSorted( cache, &key, dns_cache_compare ) );
}
static tr_dns_result
dns_cache_lookup( struct tr_web_task * task, const char * host, const char ** resolved )
{
tr_dns_result result = TR_DNS_UNTESTED;
if( task->session->web != NULL )
{
struct dns_cache_item key;
struct dns_cache_item * item;
tr_ptrArray * cache = &task->session->web->dns_cache;
key.host = (char*) host;
item = tr_ptrArrayFindSorted( cache, &key, dns_cache_compare );
/* has the ttl expired? */
if( ( item != NULL ) && ( item->expiration <= tr_time( ) ) )
{
dns_cache_clear_entry( cache, host );
item = NULL;
}
if( item != NULL )
{
result = item->success ? TR_DNS_OK : TR_DNS_FAIL;
if( result == TR_DNS_OK )
{
*resolved = item->resolved_host;
dbgmsg( "found cached dns entry for \"%s\": %s", host, *resolved );
}
}
}
return result;
}
static void
dns_cache_set_fail( struct tr_web_task * task, const char * host )
{
if( task->session->web != NULL )
{
struct dns_cache_item * item;
tr_ptrArray * cache = &task->session->web->dns_cache;
dns_cache_clear_entry( cache, host );
item = tr_new( struct dns_cache_item, 1 );
item->host = tr_strdup( host );
item->resolved_host = NULL;
item->expiration = tr_time( ) + MIN_DNS_CACHE_TIME;
item->success = FALSE;
tr_ptrArrayInsertSorted( cache, item, dns_cache_compare );
}
}
static const char*
dns_cache_set_name( struct tr_web_task * task, const char * host,
const char * resolved, int ttl )
{
char * ret = NULL;
ttl = MAX( MIN_DNS_CACHE_TIME, ttl );
if( task->session->web != NULL )
{
struct dns_cache_item * item;
tr_ptrArray * cache = &task->session->web->dns_cache;
dns_cache_clear_entry( cache, host );
item = tr_new( struct dns_cache_item, 1 );
item->host = tr_strdup( host );
item->resolved_host = tr_strdup( resolved );
item->expiration = tr_time( ) + ttl;
item->success = TRUE;
tr_ptrArrayInsertSorted( cache, item, dns_cache_compare );
ret = item->resolved_host;
dbgmsg( "adding dns cache entry for \"%s\": %s", host, resolved );
}
return ret;
}
/***
****
***/
static size_t
writeFunc( void * ptr, size_t size, size_t nmemb, void * vtask )
{
const size_t byteCount = size * nmemb;
struct tr_web_task * task = vtask;
evbuffer_add( task->response, ptr, byteCount );
dbgmsg( "wrote %zu bytes to task %p's buffer", byteCount, task );
return byteCount;
}
static int
sockoptfunction( void * vtask, curl_socket_t fd, curlsocktype purpose UNUSED )
{
struct tr_web_task * task = vtask;
const tr_bool isScrape = strstr( task->url, "scrape" ) != NULL;
const tr_bool isAnnounce = strstr( task->url, "announce" ) != NULL;
/* announce and scrape requests have tiny payloads. */
if( isScrape || isAnnounce )
{
const int sndbuf = 1024;
const int rcvbuf = isScrape ? 2048 : 3072;
setsockopt( fd, SOL_SOCKET, SO_SNDBUF, &sndbuf, sizeof(sndbuf) );
setsockopt( fd, SOL_SOCKET, SO_RCVBUF, &rcvbuf, sizeof(rcvbuf) );
}
/* return nonzero if this function encountered an error */
return 0;
}
static int
getCurlProxyType( tr_proxy_type t )
{
if( t == TR_PROXY_SOCKS4 ) return CURLPROXY_SOCKS4;
if( t == TR_PROXY_SOCKS5 ) return CURLPROXY_SOCKS5;
return CURLPROXY_HTTP;
}
static int
getTimeoutFromURL( const char * url )
{
if( strstr( url, "scrape" ) != NULL ) return 30;
if( strstr( url, "announce" ) != NULL ) return 120;
return 240;
}
static void task_timeout_cb( int fd UNUSED, short what UNUSED, void * task );
static void task_finish( struct tr_web_task * task, long response_code );
static void
addTask( void * vtask )
{
struct tr_web_task * task = vtask;
const tr_session * session = task->session;
if( ( session == NULL ) || ( session->web == NULL ) )
return;
if( !task->resolved_host )
{
dbgmsg( "couldn't resolve host for \"%s\"... task failed", task->url );
task_finish( task, 0 );
}
else
{
CURL * e = curl_easy_init( );
struct tr_web * web = session->web;
const int timeout = getTimeoutFromURL( task->url );
const long verbose = getenv( "TR_CURL_VERBOSE" ) != NULL;
const char * user_agent = TR_NAME "/" SHORT_VERSION_STRING;
/* insert the resolved host into the URL s.t. curl's DNS won't block
* even if -- like on most OSes -- it wasn't built with C-Ares :(
* "http://www.craptrackular.org/announce?key=val&key2=..." becomes
* "http://127.0.0.1/announce?key=val&key2=..." */
{
char * host;
struct evbuffer * buf = evbuffer_new( );
char * pch = strstr( task->url, task->host );
char * tail = pch + strlen( task->host );
evbuffer_add( buf, task->url, pch - task->url );
evbuffer_add_printf( buf, "%s", task->resolved_host );
evbuffer_add_printf( buf, "%s", tail );
task->resolved_url = tr_strndup( EVBUFFER_DATA( buf ), EVBUFFER_LENGTH( buf ) );
dbgmsg( "old url: \"%s\" -- new url: \"%s\"", task->url, task->resolved_url );
evbuffer_free( buf );
/* Manually add a Host: argument that refers to the true URL */
if( ( ( task->port <= 0 ) ) ||
( ( task->port == 80 ) && !strncmp( task->url, "http://", 7 ) ) ||
( ( task->port == 443 ) && !strncmp( task->url, "https://", 8 ) ) )
host = tr_strdup_printf( "Host: %s", task->host );
else
host = tr_strdup_printf( "Host: %s:%d", task->host, task->port );
task->slist = curl_slist_append( NULL, host );
task->slist = curl_slist_append( task->slist, "Accept:" );
curl_easy_setopt( e, CURLOPT_HTTPHEADER, task->slist );
tr_free( host );
}
dbgmsg( "adding task #%lu [%s]", task->tag, task->resolved_url ? task->resolved_url : task->url );
if( !task->range && session->isProxyEnabled ) {
curl_easy_setopt( e, CURLOPT_PROXY, session->proxy );
curl_easy_setopt( e, CURLOPT_PROXYAUTH, CURLAUTH_ANY );
curl_easy_setopt( e, CURLOPT_PROXYPORT, session->proxyPort );
curl_easy_setopt( e, CURLOPT_PROXYTYPE,
getCurlProxyType( session->proxyType ) );
}
if( !task->range && session->isProxyAuthEnabled ) {
char * str = tr_strdup_printf( "%s:%s", session->proxyUsername,
session->proxyPassword );
curl_easy_setopt( e, CURLOPT_PROXYUSERPWD, str );
tr_free( str );
}
task->easy = e;
task->multi = web->multi;
/* use our own timeout instead of CURLOPT_TIMEOUT because the latter
* doesn't play nicely with curl_multi. See curl bug #2501457 */
task->timer_event_isSet = TRUE;
evtimer_set( &task->timer_event, task_timeout_cb, task );
tr_timerAdd( &task->timer_event, timeout, 0 );
curl_easy_setopt( e, CURLOPT_SOCKOPTFUNCTION, sockoptfunction );
curl_easy_setopt( e, CURLOPT_SOCKOPTDATA, task );
curl_easy_setopt( e, CURLOPT_WRITEDATA, task );
curl_easy_setopt( e, CURLOPT_WRITEFUNCTION, writeFunc );
curl_easy_setopt( e, CURLOPT_DNS_CACHE_TIMEOUT, MIN_DNS_CACHE_TIME );
curl_easy_setopt( e, CURLOPT_FOLLOWLOCATION, 1L );
curl_easy_setopt( e, CURLOPT_AUTOREFERER, 1L );
curl_easy_setopt( e, CURLOPT_PRIVATE, task );
curl_easy_setopt( e, CURLOPT_SSL_VERIFYHOST, 0L );
curl_easy_setopt( e, CURLOPT_SSL_VERIFYPEER, 0L );
curl_easy_setopt( e, CURLOPT_URL, task->resolved_url ? task->resolved_url : task->url );
curl_easy_setopt( e, CURLOPT_USERAGENT, user_agent );
curl_easy_setopt( e, CURLOPT_VERBOSE, verbose );
if( web->haveAddr )
curl_easy_setopt( e, CURLOPT_INTERFACE, tr_ntop_non_ts( &web->addr ) );
if( task->range )
curl_easy_setopt( e, CURLOPT_RANGE, task->range );
if( curl_multi_add_handle( web->multi, e ) == CURLM_OK )
++web->taskCount;
}
}
static void
dns_ipv6_done_cb( int err, char type, int count, int ttl, void * addresses, void * vtask )
{
struct tr_web_task * task = vtask;
if( !err && task->host && ( count>0 ) && ( ttl>=0 ) && ( type==DNS_IPv6_AAAA ) )
{
int i;
char buf[INET6_ADDRSTRLEN+1];
struct in6_addr *in6_addrs = addresses;
for( i=0; i<count; ++i ) {
const char * b = inet_ntop(AF_INET6, &in6_addrs[i], buf,sizeof(buf));
if( b != NULL ) {
/* FIXME: is there a better way to tell which one to use if count > 1? */
task->resolved_host = dns_cache_set_name( task, task->host, b, ttl );
break;
}
}
}
if( task->resolved_host == NULL )
dns_cache_set_fail( task, task->host );
addTask( task );
}
static void
dns_ipv4_done_cb( int err, char type, int count, int ttl, void * addresses, void * vtask )
{
struct tr_web_task * task = vtask;
if( !err && task->host && ( count>0 ) && ( ttl>=0 ) && ( type==DNS_IPv4_A ) )
{
struct in_addr * in_addrs = addresses;
const char * resolved = inet_ntoa( in_addrs[0] );
task->resolved_host = dns_cache_set_name( task, task->host, resolved, ttl );
/* FIXME: if count > 1, is there a way to decide which is best to use? */
}
if( ( task->resolved_host != NULL )
|| ( task->host == NULL )
|| evdns_resolve_ipv6( task->host, 0, dns_ipv6_done_cb, task ) )
dns_ipv6_done_cb( DNS_ERR_UNKNOWN, DNS_IPv6_AAAA, 0, 0, NULL, task );
}
static void
doDNS( void * vtask )
{
tr_address addr;
int port = -1;
char * host = NULL;
struct tr_web_task * task = vtask;
tr_dns_result lookup_result = TR_DNS_UNTESTED;
assert( task->resolved_host == NULL );
if( !tr_httpParseURL( task->url, -1, &host, &port, NULL ) )
{
task->port = port;
task->host = host;
/* If 'host' is an IPv4 or IPv6 address in text form, use it as-is.
* Otherwise, see if its resolved name is in our DNS cache */
if( tr_pton( task->host, &addr ) != NULL )
{
task->resolved_host = task->host;
lookup_result = TR_DNS_OK;
}
else
{
lookup_result = dns_cache_lookup( task, host, &task->resolved_host );
}
}
if( lookup_result != TR_DNS_UNTESTED )
{
addTask( task );
}
else if( !host || evdns_resolve_ipv4( host, 0, dns_ipv4_done_cb, task ) )
{
dns_ipv4_done_cb( DNS_ERR_UNKNOWN, DNS_IPv4_A, 0, 0, NULL, task );
}
}
/***
****
***/
static void
task_finish( struct tr_web_task * task, long response_code )
{
dbgmsg( "finished web task %lu; got %ld", task->tag, response_code );
if( task->done_func != NULL )
task->done_func( task->session,
response_code,
EVBUFFER_DATA( task->response ),
EVBUFFER_LENGTH( task->response ),
task->done_func_user_data );
task_free( task );
}
static void
remove_task( struct tr_web_task * task )
{
long code;
curl_easy_getinfo( task->easy, CURLINFO_RESPONSE_CODE, &code );
curl_multi_remove_handle( task->multi, task->easy );
curl_easy_cleanup( task->easy );
task_finish( task, code );
}
static void
task_timeout_cb( int fd UNUSED, short what UNUSED, void * task )
{
remove_task( task );
}
static void
remove_finished_tasks( tr_web * g )
{
CURLMsg * msg;
int msgs_left;
while(( msg = curl_multi_info_read( g->multi, &msgs_left ))) {
if(( msg->msg == CURLMSG_DONE ) && ( msg->easy_handle != NULL )) {
struct tr_web_task * task;
CURL * e = msg->easy_handle;
curl_easy_getinfo( e, CURLINFO_PRIVATE, (void*)&task );
assert( e == task->easy );
remove_task( task );
}
}
}
static void
restart_timer( tr_web * g )
{
dbgmsg( "adding a timeout for %.1f seconds from now", g->timer_msec/1000.0 );
evtimer_del( &g->timer_event );
tr_timerAddMsec( &g->timer_event, g->timer_msec );
}
static void
tr_multi_perform( tr_web * g, int fd, int curl_what )
{
CURLMcode m;
dbgmsg( "check_run_count: %d taskCount", g->taskCount );
/* invoke libcurl's processing */
do
m = curl_multi_socket_action( g->multi, fd, curl_what, &g->taskCount );
while( m == CURLM_CALL_MULTI_SOCKET );
remove_finished_tasks( g );
if( g->closing && !g->taskCount )
web_free( g );
else
restart_timer( g );
}
/* libevent says that sock is ready to be processed, so wake up libcurl */
static void
event_cb( int fd, short ev_what, void * g )
{
int curl_what = 0;
if( ev_what & EV_READ ) curl_what |= CURL_POLL_IN;
if( ev_what & EV_WRITE ) curl_what |= CURL_POLL_OUT;
tr_multi_perform( g, fd, curl_what );
}
/* CURLMOPT_SOCKETFUNCTION */
static int
sock_cb( CURL * e UNUSED, curl_socket_t fd, int curl_what,
void * vweb, void * vevent )
{
/*static int num_events = 0;*/
struct tr_web * web = vweb;
struct event * io_event = vevent;
dbgmsg( "sock_cb: curl_what %d, fd %d, io_event %p",
curl_what, (int)fd, io_event );
if( io_event != NULL )
event_del( io_event );
if( curl_what & ( CURL_POLL_IN | CURL_POLL_OUT ) )
{
const short ev_what = EV_PERSIST
| (( curl_what & CURL_POLL_IN ) ? EV_READ : 0 )
| (( curl_what & CURL_POLL_OUT ) ? EV_WRITE : 0 );
if( io_event == NULL ) {
io_event = tr_new0( struct event, 1 );
curl_multi_assign( web->multi, fd, io_event );
/*fprintf( stderr, "+1 io_events to %d\n", ++num_events );*/
}
dbgmsg( "enabling (libevent %hd, libcurl %d) on io_event %p, fd %d",
ev_what, curl_what, io_event, fd );
event_set( io_event, fd, ev_what, event_cb, web );
assert( io_event->ev_base != NULL );
event_add( io_event, NULL );
}
if( ( io_event != NULL ) && ( curl_what & CURL_POLL_REMOVE ) )
{
memset( io_event, TR_MEMORY_TRASH, sizeof( struct event ) );
tr_free( io_event );
/*fprintf( stderr, "-1 io_events to %d\n", --num_events );*/
}
return 0; /* libcurl documentation: "The callback MUST return 0." */
}
/* libevent says that timer_msec have passed, so wake up libcurl */
static void
libevent_timer_cb( int fd UNUSED, short what UNUSED, void * g )
{
dbgmsg( "libevent timer is done" );
tr_multi_perform( g, CURL_SOCKET_TIMEOUT, 0 );
}
/* libcurl documentation: "If 0, it means you should proceed immediately
* without waiting for anything. If it returns -1, there's no timeout at all
* set ... (but) you must not wait too long (more than a few seconds perhaps)
* before you call curl_multi_perform() again." */
static void
multi_timer_cb( CURLM * multi UNUSED, long timer_msec, void * vg )
{
tr_web * g = vg;
g->timer_msec = timer_msec > 0 ? timer_msec : DEFAULT_TIMER_MSEC;
if( timer_msec < 1 )
tr_multi_perform( g, CURL_SOCKET_TIMEOUT, 0 );
else
restart_timer( g );
}
/****
*****
****/
void
tr_webRun( tr_session * session,
const char * url,
const char * range,
tr_web_done_func done_func,
void * done_func_user_data )
{
if( session->web != NULL )
{
static unsigned long tag = 0;
struct tr_web_task * task = tr_new0( struct tr_web_task, 1 );
task->session = session;
task->url = tr_strdup( url );
task->range = tr_strdup( range );
task->done_func = done_func;
task->done_func_user_data = done_func_user_data;
task->tag = ++tag;
task->response = evbuffer_new( );
tr_runInEventThread( session, doDNS, task );
}
}
void
tr_webSetInterface( tr_web * web, const tr_address * addr )
{
if(( web->haveAddr = ( addr != NULL )))
web->addr = *addr;
}
tr_web*
tr_webInit( tr_session * session )
{
tr_web * web;
/* try to enable ssl for https support; but if that fails,
* try a plain vanilla init */
if( curl_global_init( CURL_GLOBAL_SSL ) )
curl_global_init( 0 );
web = tr_new0( struct tr_web, 1 );
web->dns_cache = TR_PTR_ARRAY_INIT;
web->session = session;
web->timer_msec = DEFAULT_TIMER_MSEC; /* overwritten by multi_timer_cb() */
evtimer_set( &web->timer_event, libevent_timer_cb, web );
web->multi = curl_multi_init( );
evdns_init( );
curl_multi_setopt( web->multi, CURLMOPT_SOCKETDATA, web );
curl_multi_setopt( web->multi, CURLMOPT_SOCKETFUNCTION, sock_cb );
curl_multi_setopt( web->multi, CURLMOPT_TIMERDATA, web );
curl_multi_setopt( web->multi, CURLMOPT_TIMERFUNCTION, multi_timer_cb );
return web;
}
void
tr_webClose( tr_web ** web_in )
{
tr_web * web = *web_in;
*web_in = NULL;
if( web->taskCount < 1 )
web_free( web );
else
web->closing = 1;
}
/*****
******
******
*****/
const char *
tr_webGetResponseStr( long code )
{
switch( code )
{
case 0: return "No Response";
case 101: return "Switching Protocols";
case 200: return "OK";
case 201: return "Created";
case 202: return "Accepted";
case 203: return "Non-Authoritative Information";
case 204: return "No Content";
case 205: return "Reset Content";
case 206: return "Partial Content";
case 300: return "Multiple Choices";
case 301: return "Moved Permanently";
case 302: return "Found";
case 303: return "See Other";
case 304: return "Not Modified";
case 305: return "Use Proxy";
case 306: return "(Unused)";
case 307: return "Temporary Redirect";
case 400: return "Bad Request";
case 401: return "Unauthorized";
case 402: return "Payment Required";
case 403: return "Forbidden";
case 404: return "Not Found";
case 405: return "Method Not Allowed";
case 406: return "Not Acceptable";
case 407: return "Proxy Authentication Required";
case 408: return "Request Timeout";
case 409: return "Conflict";
case 410: return "Gone";
case 411: return "Length Required";
case 412: return "Precondition Failed";
case 413: return "Request Entity Too Large";
case 414: return "Request-URI Too Long";
case 415: return "Unsupported Media Type";
case 416: return "Requested Range Not Satisfiable";
case 417: return "Expectation Failed";
case 500: return "Internal Server Error";
case 501: return "Not Implemented";
case 502: return "Bad Gateway";
case 503: return "Service Unavailable";
case 504: return "Gateway Timeout";
case 505: return "HTTP Version Not Supported";
default: return "Unknown Error";
}
}
void
tr_http_escape( struct evbuffer * out,
const char * str, int len, tr_bool escape_slashes )
{
int i;
if( ( len < 0 ) && ( str != NULL ) )
len = strlen( str );
for( i = 0; i < len; i++ ) {
if( str[i] == ',' || str[i] == '-' || str[i] == '.'
|| ( '0' <= str[i] && str[i] <= '9' )
|| ( 'A' <= str[i] && str[i] <= 'Z' )
|| ( 'a' <= str[i] && str[i] <= 'z' )
|| ( str[i] == '/' && !escape_slashes ) )
evbuffer_add( out, &str[i], 1 );
else
evbuffer_add_printf( out, "%%%02X", (unsigned)(str[i]&0xFF) );
}
}
char *
tr_http_unescape( const char * str, int len )
{
char * tmp = curl_unescape( str, len );
char * ret = tr_strdup( tmp );
curl_free( tmp );
return ret;
}
Reference in New Issue View Git Blame Copy Permalink